The antigenic structure of adult human hemoglobin will be studied. Chemical derivates of hemoglobin will be prepared, purified, characterized and their conformation and immunochemistry studied in detail. Immunochemical and conformational studies will also be carried out on homogeneous peptide fragments prepared from hemoglobin by specific chemical and enzymic cleavage procedures. The antigenic structure of sperm-shale myoglobin which we have recently completed for early-course antisera in rabbits and goats will now be used as a first available protein model to study the influence, if any, of several factors on the in vivo immune response to a native protein antigen. Research will continue to devise new chemical modification and cleavage reactions of proteins. BIBLIOGRAPHIC REFERENCES: Immunochemistry of Serum Albumin. II. Isolation and Characterization of a Fragment from the First Third of the Molecule Carrying Almost All the Antigenic Reactivity of the Protein. M.Z. Atassi, A.F.S.A. Habeeb and C.-L. Lee Immunochemistry (1976), 13, 547-555. Enzymic and Immunochemical Properties of Lysozyme. XV. Delineation of the Reactive Site Around the Two Central Disulfides of Lysozyme by Immunochemical Studies of Novel Synthetic Peptides that Contain Diglycyl Bridges Instead of Disulfides. C.-L. Lee, R.-C. Pai and M.Z. Atassi Immunochemistry (1976), 13, 681-687.